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1.
The endangered snail kite (Rostrhamus sociabilis) feeds primarily on the freshwater apple snail (Pomacea paludosa) in Florida. The nonindigenous, floating water hyacinth (Eichhornia crassipes) and water lettuce (Pistia stratiotes) impede kites from finding snails. Effective control of these aquatic plants in the littoral zone of central and south Florida lakes benefits kites by maintaining open foraging habitat. However, incidental herbicide spraying of nesting substrates result in nest collapse when kites breed in nonwoody, emergent plants [cattail (Typha spp.) and giant bulrush (Scirpus validus)] in the outer littoral zone during lower lake levels. Many endangered species recovery plans and their implementation have experienced problems due to inaction and/or noncooperation by various governmental agencies and their personnel. Herein, we describe the development and implementation of a buffer zone strategy to prevent secondary impacts from an aquatic plant control program to snail kites nesting on lakes in central and south Florida. A strategy was jointly developed by personnel of five state and federal agencies to control herbicide application near kite nesting areas during the normal breeding season. Although requiring various modifications during its implementation, this cooperative effort successfully integrated aquatic plant control objectives with snail kite conservation on Lake Okeechobee during 1988. The program was expanded the following year to lakes Kissimmee and Tohopekaliga. Since the implementation of the snail kite impact preclusion program, no nest loss was attributed to incidental herbicide applications on lakes Okeechobee, Kissimmee, and Tohopekaliga.  相似文献   

2.
Analysis tools that combine large spatial and temporal scales are necessary for efficient management of wildlife species, such as the burrowing owl (Athene cunicularia). We assessed the ability of Ripley’s K-function analysis integrated into a geographic information system (GIS) to determine changes in burrowing owl nest clustering over two years at NASA Ames Research Center. Specifically, we used these tools to detect changes in spatial and temporal nest clustering before, during, and after conducting management by mowing to maintain low vegetation height at nest burrows. We found that the scale and timing of owl nest clustering matched the scale and timing of our conservation management actions over a short time frame. While this study could not determine a causal link between mowing and nest clustering, we did find that Ripley’s K and GIS were effective in detecting owl nest clustering and show promise for future conservation uses.  相似文献   

3.
ABSTRACT: In the absence of detailed outlines such as those characteristic of the National Pollution Discharge Elimination System permit program, Nonpoint source pollution control is being initiated in a variety of ways in different states. In California, Regional Water Quality Control Boards play a strong enforcement role in point source control, but agricultural Nonpoint source needs are still being evaluated. Tentative approval of State Board of Forestry Forest Practice Rules by the State Water Resources Control Board has the potential of bringing Nonpoint control to all State and private forestry operations in the state. Wisconsin had developed an agricultural Nonpoint control program which emphasizes a state-wide policy of selecting priority watersheds under the administration of the state Department of Natural Resources, and developing implementation programs under the guidance of local county Land Conservation Committees. The Priority Watershed program institutes BMP's with cost-share funds authorized by the legislature. Wisconsin had not seen a problem in silvicultural activities, and has developed no statewide control program in that area. Common to effective land use control in both states is a state-level policy implemented by agencies within the state. This pattern may be the model for successful programs as development of areawide management strategies continue.  相似文献   

4.
The American crocodile is a rare and endangered species, the range of which has contracted to disjunct locations such as Hispaniola, Jamaica, Cuba, Panama, and southern Florida. In an attempt to determine what factors might be limiting population growth, an extensive collaborative research program was conducted in 1978–82 in southern Florida. Limiting factors explicitly studied included climate, hurricanes, population dispersion, nesting habitat, fertility, predation, nest chamber environment, juvenile survivorship, artificial mortality, disturbance, and environmental contamination. No single natural factor limits the population, although in concert various factors result in low adult recruitment rates. Such natural limitations explain the natural rarity of this tropical species at the temperate limits of its range. Two artificial sources of mortality are death of adults on roads and the flooding of nests by high groundwater tables. These sources of mortality are potentially controllable by the appropriate management agencies. Active management, by such means as protection of individuals, habitat preservation and enhancement, nest site protection, and captive breeding, is also appropriate for assuring the survival of a rare species. The American crocodile has survived in southern Florida in face of extensive human occupancy of parts of its former nesting habitat, demonstrating the resilience of a threatened species. This case history illustrates the efficacy of conducting research aimed at testing specific management hypotheses, the importance of considering biographical constraints limiting population status in peripheral populations, the need for active management of rare species, and the role of multiple reserves in a conservation and management strategy.  相似文献   

5.
The origin of the grassy balds of the Great Smoky Mountains is examined. Some of the areas were cleared by settlers. Grazing by sheep and cattle and the cutting of trees were probably the most important factors in maintaining the grass sward; fire apparently was not used.Vegetation survey plots indicated that little of the original balds' area was still grassy and that most of the invading trees and shrubs could be expected to sprout if cut or burned. Areas presently trampled or mowed had a flora similar to a bald that was still grazed. High-elevation burn scars had many species in common with the grassy balds but had dissimilar community structures; therefore, a policy favoring natural fires would be unlikely to encourage maintanence or formation of grassy balds.The management of open grassy areas on National Forest lands was investigated. Burning was the favored technique, although hand cutting, mowing, and grazing were used. The results of testing various management practices on Gregory Bald are reviewed in terms of cost, impact, and historical authenticity. Implications for park management are discussed.  相似文献   

6.
Drawing from experiences gained from the development and implementation of four approved habitat conservation plans (HCPs), I describe the goals and strategies used by the nine local government members of the Riverside County Habitat Conservation Agency (RCHCA) to reconcile conflicts among a rapidly growing population and the need to conserve the habitat of a number of declining wildlife species in western Riverside County, California. Several important goals have been pursued by RCHCA member governments in their sponsorship of multiple-species habitat conservation plans (MSHCPs), including (1) establishing certainty and control over future uses of land; (2) eliminating project-by-project negotiations with federal and state wildlife agencies; (3) coordinating mitigation obligations under the Endangered Species Act, Clean Water Act, California Environmental Quality Act, and other federal and state laws; (4) reducing conflict and litigation resulting from land development activities; and (5) ensuring that wildlife conservation activities are conducted in a manner that permits local governments to perform those functions necessary to maintain public health, safety, and welfare. I also describe the emergence of strategies by local governments to achieve MSHCP goals, including (1) use of an inclusive planning process that seeks to build consensus among affected interests; (2) extensive involvement of federal and state wildlife agencies in the preparation of MSHCP documents; (3) management of public lands to support MSHCP conservation objectives; (4) encouragement of voluntary conservation by private property owners through incentive programs; and (5) active solicitation of federal and state funding for MSHCP implementation activities.  相似文献   

7.
Adaptive management (AM) is the process of implementing land management activities in incremental steps and evaluating whether desired outcomes are being achieved at each step. If conditions deviate substantially from predictions, management activities are adjusted to achieve the desired outcomes. Thus, AM is a kind of monitoring, an activity that land management agencies have done poorly for the most part, at least with respect to ground-based monitoring. Will they do better in the future? We doubt it unless costs, personnel, and future commitment are seriously addressed. Because ecosystem responses to management impacts can ripple into the distant future, monitoring programs that address only the near future (e.g., 10–20 years), are probably unreliable for making statements about resource conditions in the distant future. We give examples of this. Feedback loops between ecosystem response and adjustment of management actions are often broken, and therefore AM again fails. Successful ground-based monitoring must address these and other points that agencies commonly ignore. As part of the solution, publics distrustful of agency activities should be included in any monitoring program.  相似文献   

8.
The lower Roanoke River in North Carolina, USA, has been regulated by a series of dams since the 1950s. This river and its floodplain have been identified by The Nature Conservancy, the US Fish and Wildlife Service, and the State of North Carolina as critical resources for the conservation of bottomland hardwoods and other riparian and in-stream biota and communities. Upstream dams are causing extended floods in the growing season for bottomland hardwood forests, threatening their survival. A coalition of stakeholders including public agencies and private organizations is cooperating with the dam managers to establish an active adaptive management program to reduce the negative impacts of flow regulation, especially extended growing season inundation, on these conservation targets. We introduce the lower Roanoke River, describe the regulatory context for negotiating towards an active adaptive management program, present our conservation objective for bottomland hardwoods, and describe investigations in which we successfully employed a series of models to develop testable management hypotheses. We propose adaptive management strategies that we believe will enable the bottomland hardwoods to regenerate and support their associated biota and that are reasonable, flexible, and economically sustainable.  相似文献   

9.
ABSTRACT: The elimination of groundwater overdraft was a key feature of the 1980 Arizona Groundwater Management Act. To achieve this goal, the Arizona Department of Water Resources identified several Active Management Areas and developed urban, industrial, and agricultural water conservation plans. This study examines the reductions in groundwater use through agricultural water conservation in the Phoenix Active Management Area (AMA). Linear programming models are developed to analyze changes in groundwater use and net returns to agriculture over a 38-year period, 1990 to 2025, for farming areas in the Phoenix AMA. Results indicate that the agricultural conservation program provides only modest groundwater savings under a wide range of scenarios. The low level of savings is partly due to the current economically efficient use of water. Other policy measures such as retiring agricultural land may be necessary if the Phoenix AMA is to meet its overdraft reduction goals; even if urban water conservation goals are met.  相似文献   

10.
ABSTRACT: The Louisiana Environmental Management System (LEMS) is a data processing program developed to aid the Louisiana Joint Legislative Committee on Environmental Quality in decisions leading to resources legislation. Serving as a central data collection and retrieval point for various agencies, the LEMS will maintain assembled information on the location of monitoring stations and coordinate the files of user agencies with data on: land use; air and water quality; meteorological, climatological, and hydrological phenomena; vegetation; fish and wildlife conservation; population; and economics. This data is geographically stored in relation to the state plane coordinate system. For decision making, all pertinent hydrologic, topographic, engineering, cadastral, and other information from separate sources can be automatically mapped as a combined overlay to one of three chosen scales. Land-use patterns are the input data for iterative analyses of present conditions and simulated future human activities for assessing the environmental impact of proposed multiple-purpose water resource developments.  相似文献   

11.
Fishers and small-scale fisheries worldwide have been marginalized historically. Now it is clear that integrating fishers in management processes is key to resource conservation, but it is less clear how to do it. Here, based on a literature review and new information, we present and analyze a case in which the participation of fishers in the management process was crucial in recovering an overexploited small-scale fishery for the pirarucu (Arapaima spp.) in the Amazon Basin, Brazil. In 8 years of experimental management, from 1999 to 2006, the population of pirarucu increased 9-fold (from about 2200 to 20,650 individuals), harvest quotas increased 10-fold (from 120 to 1249 individuals), and fishers’ participation in the management process increased and they benefited from increased monetary returns. Additionally, the number of communities conducting the management scheme increased from 4 in 1999 to 108 in 2006, following the demands of fishers and regional government agencies. Based on our analysis, we suggest that the participation of fishers in the management of other small-scale fisheries in the world can be improved by focusing on (1) applying the knowledge and skills of fishers in resource monitoring and management, (2) bridging knowledge systems among all involved stakeholders, (3) collaborating with fishers that are interested in, and capable of conducting, resource conservation schemes, and (4) conducting management under conditions of uncertainty.  相似文献   

12.
Recovery planning is a key component of many threatened species conservation initiatives and can be a powerful awareness raising tool. One of the largest impediments to conservation efforts in the Pacific region however, is the lack of ecological data and its subsequent effects on the development of feasible and useful recovery plans for threatened species. Without these plans, the understaffed, underfunded and often technically ill-equipped conservation agencies face huge difficulties in planning, prioritizing and conducting conservation activities to adequately protect biodiversity. The Fiji sago palm, Metroxylon vitiense, is an endemic endangered palm species whose survival is heavily dependent on a feasible species recovery plan. It is geographically restricted and threatened by habitat destruction and overexploitation for thatch for the tourism industry and palm heart consumption by local consumers. Despite its threatened status, M. vitiense is not currently protected by national or international legislation. Recent field surveys and extensive stakeholder consultation have resulted in the production of a species recovery plan highlighting the importance of the species and advocating sustainable harvesting rather than complete bans to promote conservation. This article summarizes the recovery plan and its current effects on the status of M. vitiense in Fiji. We also discuss the role of different stakeholders in the conservation of M. vitiense, including the absence of significant behavioral changes by the largest consumer - the tourism industry, and the importance of recovery plans for biodiversity conservation in the Pacific.  相似文献   

13.
Power line rights-of-way provide a major portion of the shrub habitat in New York. Since this habitat type is on the decline, many of the birds dependent on shrub habitat are also declining. The methods used to control right-of-way vegetation could therefore have serious impacts on several birds of conservation concern. Since New York is increasingly using selective herbicide treatments in vegetation management, we sought to investigate the potential impacts of these treatments on nesting birds. The study looked at plots in two adjacent rights-of-way before and after a selective herbicide treatment in one of the rights-of-way. We investigated three bird species: alder flycatcher (Empidonax alnorum), chestnut-sided warbler (Dendroica pensylvanica), and gray catbird (Dumetella carolinensis). All three species exhibited a preference for shrub vegetation around nest sites. The selective herbicide treatment did not significantly decrease that shrub vegetation, and neither the density nor the nesting success of the three species declined following the treatment. We conclude that selective herbicide vegetation management encourages the development of shrub habitat without negatively impacting the birds nesting in the habitat.  相似文献   

14.
15.
ABSTRACT: Unrelenting pressure on limited surface water supplies requires increasingly sophisticated water management approaches. Climate forecasts of seasonal precipitation and temperature are potentially useful, but the operational water management community currently underutilizes them. However, some agencies in Arizona took unprecedented advantage of forecasts for a potentially wet winter during the 1997–1998 El Niño event. This study investigates use of this information through a series of semi‐structured in‐depth interviews with key personnel from agencies responsible for emergency management and water supply; their jurisdictions ranged from urban to rural and local to regional. Interviews investigated information acquisition, interpretation, and incorporation into specific decisions and actions. While unprecedented actions were taken by some water management agencies and no agencies implemented inappropriate measures, some missed opportunities for more effective response, primarily through inaction. This study reveals a variety of technical factors and institutional characteristics affecting forecast use. Study findings emphasize the need for: (a) closer ongoing relationships between forecast producers and users, (b) increased institutional flexibility to exploit the increasing skill of seasonal climate forecasts, (c) demonstration projects of effective forecast use, and (d) a regional forum to facilitate information transfer between the hydro‐climatic research community and operational water managers.  相似文献   

16.
Southard, Gregory M., Loraine T. Fries, and Aaron Barkoh, 2010. Prymnesium parvum: The Texas Experience. Journal of the American Water Resources Association (JAWRA) 46(1):14-23. DOI: 10.1111/j.1752-1688.2009.00387.x Abstract: Golden alga Prymnesium parvum was first identified in Texas during a fish kill investigation on the Pecos River in 1985. Since then golden alga kills occurred sporadically in a variety of waters in the western part of the state until 2001 when the alga became endemic in the Brazos, Canadian, Colorado, Red, and Rio Grande river systems, including the water supplies of two public fish hatcheries, the Possum Kingdom and Dundee state fish hatcheries. The increasing area adversely affected by the alga and frequent massive fish kills heightened public and political awareness and concerns regarding the ecological and economic impacts of P. parvum blooms. The Texas Parks and Wildlife Department (TPWD), the wildlife conservation agency of the state, responded to these concerns with a program to assess the ecological and economic impacts and to develop management options. To date 33 water bodies have been affected and losses are conservatively estimated at 34 million fish valued at US$13 million. Several sport fisheries, including smallmouth bass Micropterus dolomieu, striped bass Morone saxatilis, channel catfish Ictalurus punctatus, and blue catfish Ictalurus furcatus, have been severely affected. Additionally, 26 imperiled fish species occur in the affected water basins and some have been adversely affected. Economic losses associated with reduced fishing and other water-based recreational activities appear considerable. The combined economic losses to three counties (Palo Pinto, Stephens, and Young) surrounding Possum Kingdom reservoir for 2001 and 2003 were estimated at US$2.8 million and US$1.1 million, respectively. This paper describes how the TPWD responded to public and political concerns relative to the emergence of golden alga, its harmful effects to fisheries, and its historic and current statewide distribution.  相似文献   

17.
ABSTRACT: The Biscayne Aquifer is the sole source of drinking water for approximately three million residents of southeast Florida. Nine hazardous waste sites on the EPA National Priority List overlie this aquifer. Extensive investigation of an 80 square-mile area in metropolitan Miami detected low to moderate levels of toxic contaminants in the ground water, with volatile organic chemicals the most prevalent. The Centers for Disease Control concluded that contamination of the aquifer within the study area poses a serious potential threat to public health. Recommendations for source control and cleanup have been partially carried out. The top few feet of soil at the Miami Drum site have been excavated and relocated; ground water encountered during excavation has been withdrawn and treated, and the Northwest 58th Street Landfill has been closed. Recovery and treatment of ground water from the contaminated area was the recommended cleanup measure and has been approved by EPA and state and local agencies. A preventive action program for the Biscayne Aquifer region was also recommended for implementation by local agencies. This program consists of regulations, waste management practices, construction and treatment guidelines, and public information activities and materials. Implementing this program will help keep the Biscayne Aquifer water drinkable far into the future.  相似文献   

18.
Given the projected threat that climate change poses to biodiversity, the need for proactive response efforts is clear. However, integrating uncertain climate change information into conservation planning is challenging, and more explicit guidance is needed. To this end, this article provides a specific example of how a risk-based approach can be used to incorporate a species’ response to climate into conservation decisions. This is shown by taking advantage of species’ response (i.e., impact) models that have been developed for a well-studied bird species of conservation concern. Specifically, we examine the current and potential impact of climate on nest survival of the Lewis’s Woodpecker (Melanerpes lewis) in two different habitats. To address climate uncertainty, climate scenarios are developed by manipulating historical weather observations to create ensembles (i.e., multiple sequences of daily weather) that reflect historical variability and potential climate change. These ensembles allow for a probabilistic evaluation of the risk posed to Lewis’s Woodpecker nest survival and are used in two demographic analyses. First, the relative value of each habitat is compared in terms of nest survival, and second, the likelihood of exceeding a critical population threshold is examined. By embedding the analyses in a risk framework, we show how management choices can be made to be commensurate with a defined level of acceptable risk. The results can be used to inform habitat prioritization and are discussed in the context of an economic framework for evaluating trade-offs between management alternatives.  相似文献   

19.
Croatia, like many other transition countries has undergone radical changes in its nature protection models. This paper discusses a historical overview, present situation and future possibilities for nature conservation in Croatia. A conservative top-down approach to nature protection was applied in the past in Croatia and is now being replaced by a prevalent bottom-up approach. Social context is crucial to introducing participatory conservation, therefore special concern is given to the perception of the local population towards protected area management in Istria as a case study in Croatia. Survey data were used to assess the conservation knowledge of local populations and their perception towards Protected Areas (PAs), leadership activities and management authorities in Istria County. This paper examines the perceptions of 313 residents living in and around six natural PAs located in Istria. The results revealed a moderate general knowledge about PAs in Istria and environmental issues, and a low awareness of institutions managing PAs, eagerness to participate in the activities of PAs and general support for the conservation cause. Understanding the perception of local residents enables the creation of feasible, long-term strategies for the implementation of participatory conservation. The research identifies the need for greater human, technical and financial efforts to strengthen the management capabilities of local agencies responsible for PAs. The process of participatory conservation optimization in Croatia is underway and world experiences must be observed in order to create a congruent, site-specific model with the best possible results.  相似文献   

20.
Managers can improve conservation of lotic systems over large geographies if they have tools to assess total watershed conditions for individual stream segments and can identify segments where conservation practices are most likely to be successful (i.e., primary management capacity). The goal of this research was to develop a suite of threat indices to help agriculture resource management agencies select and prioritize watersheds across Missouri River basin in which to implement agriculture conservation practices. We quantified watershed percentages or densities of 17 threat metrics that represent major sources of ecological stress to stream communities into five threat indices: agriculture, urban, point-source pollution, infrastructure, and all non-agriculture threats. We identified stream segments where agriculture management agencies had primary management capacity. Agriculture watershed condition differed by ecoregion and considerable local variation was observed among stream segments in ecoregions of high agriculture threats. Stream segments with high non-agriculture threats were most concentrated near urban areas, but showed high local variability. 60 % of stream segments in the basin were classified as under U.S. Department of Agriculture’s Natural Resources Conservation Service (NRCS) primary management capacity and most segments were in regions of high agricultural threats. NRCS primary management capacity was locally variable which highlights the importance of assessing total watershed condition for multiple threats. Our threat indices can be used by agriculture resource management agencies to prioritize conservation actions and investments based on: (a) relative severity of all threats, (b) relative severity of agricultural threats, and (c) and degree of primary management capacity.  相似文献   

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